Repair all HHS hosp backissues for _prop signals in nation, hhs regions

[krivard]

Cleanup from #1407: Regenerate issues where the #1399 bug was active. hhs_hosp supports as-of functionality in its params file so this should be fairly straightforward.

Affected data:

• source: hhs
• signals: confirmed_admissions_covid_1d_prop, confirmed_admissions_covid_1d_prop_7dav, sum_confirmed_suspected_admissions_covid_1d_prop, sum_confirmed_suspected_admissions_covid_1d_prop_7dav, confirmed_admissions_influenza_1d_prop, confirmed_admissions_influenza_1d_prop_7dav
• geo levels: hhs, nation
• time values: all
• issues: 20201116-20201209

[minhkhul]

Patched.